Flexible metal hose connection



`lune 2l, 1949. s. GuARNAscHELLl FLEXIBLE METAL HOSE CONNECTION Filed arch 11. 1947 Patented June 21, 1949 FLEHBLE METAL HOSE CONNECTION Stephen Guarnaschelli, Naugatuck, Conn., as-

signor to The Brockway Company, Naugatuck, Conn., a. corporation of Connecticut Application March 11, 1947, Serial No. 733,842

2 Claims. (Cl. 285-74) This invention relates to an improved method of securing standard flexible metal hose to a metal fitting or connector, and to the assembly thereby obtained.

Flexible metal hose as ordinarily employed in commerce comprises metal tubing of copper, brass, bronze or the like, having concentric or helical convolutions therein which render it readily flexible in axial planes, and provided with a cover or sheath of braided metal wire to protect the hose from injury upon contact with other objects, to prevent foreign matter from becoming lodge between the convolutions, and to improve its appearance.

The attachment of ttings or connections to the end of the aforesaid flexible metal hose has been accomplished heretofore by soldering. The fitting usually has a cup-shaped cavity for receiving the end of the hose, and solder is deposited therein to form a bond between the tting and the hose when the latter is inserted in the cavity.

Certain diiiiculties attend the operations involved in soldering such a fitting to the end of a flexible metal hose in the aforesaid manner. Thus, when the hose is cut oft, the wire braid of the sheath tends to expand at the severed end, rendering the hose exceedingly difficult to insert in the cavity of a fitting. In some cases, the braid is pushed back during insertion of the fitting so that no bond is formed between the fitting and the braid. In use, the braid then pulls outof the tting, resulting in an unsightly and impractical connection. It is therefore necessary to squeeze and hold the braid together prior to such insertion, presenting considerable inconvenience and causing loss of time in the manipulation.

Often it is necessary to heat the tting after assembly with the hose in order to melt the solder or to maintain it in molten condition long enough to form an adequate bond. When this is required, considerable danger exists of overheating the assembly and causing burning or injury to the braid or the hose.

It is an object of this invention to provide a method for soldering a fitting or connector to the end of standard flexible metal hose of the type hereinbefore described, wherein the danger of burning or weakening portions of the assembly is avoided, and the diiliculty of inserting the end of the hose in the fitting is eliminated.

It is also an object to provide a method suitable for mass production, and an assembly wherein the hose can be adequately supported 2 adjacent the soldered bond so as to reinforce the connection against failure of the bond upon fiexure of the hose.

In accordance with my invention, a relatively thin-walled metal sleeve fitting snugly over the braided sheath of the flexible metal hose is placed thereon, and after cutting off the end of the hose to align the end of the sheath and the flexible tubing, the sleeve is advanced until its end is aligned with that of the hose and its sheath. The braided sheath is thereby constricted against the tubing and confined against spreading or being pushed back on the tubing.

The fitting to which the hose is to be connected has a cavity of a diameter adapted slidably to receive the sleeve with the hose therein. If the fitting has a rearwardly extending bore or passage communicating with the cavity, the latter is closed by insertion of a pin of solderrepellent material, such as aluminum, and a quantity of solder is deposited in the base of the cavity of the fitting. The end of the hose carrying the sleeve is then inserted into the cavity so as to displace the solder. The latter rises between the sleeve and the side wall of the cavity aided by capillary attraction, and also between the braided sheath and the sleeve, entering the interstices of the braid, and likewise bonds to the end of the flexible metal tubing immersed therein. After cooling to solidify the solder, the pin is withdrawn, leaving the hose firmly soldered to the fitting.

Since the operation of inserting the hose and sleeve in the fitting requires no difilcult manipulation, and Vcan be rapidly carried out, the parts need only be heated for a minimum period to the optimum temperature for forming a solder bond, so that all danger of burning the braid or otherwise injuring the hose from overheating is avoided. In view of the convenience and ease with which the assembly operation can be carried out, it is admirably adapted for mass production.

If desired, the sleeve can be constructed to extend a substantial distance beyond the end of the fitting, thereby reinforcing the hose against iiexure adjacent the soldered bond, and preventing failure of the bond from axial flexure of the hose.

My invention will be more fully understood from the following description taken in connection with the accompanying drawing, wherein:

Figure 1 is a. side elevation of the flexible metal hose assembled with the fitting;

Fig. 2 is a view partially in axial cross-section showing the parts of Fig. 1, preparatory to assembly thereof;

Fig. 3 is a view similar to Fig. 2 showing the parts after their assembly; and

Fig. 4 is an exploded view of said parts prior to assembly thereof.

Referring to the drawings, the assembly shown therein comprises a iiexible metal hose I having a sheath II of braided copper or other metal wire, and within said sheath, a length of corrugated metal tubing I2, having helical corrugations in the illustrated embodiment. However, exible hose comprising tubing with concentric corrugations can be similarly used. A thin-cylindrical sleeve I3 of solderable metal, such as brass,

copper or bronze is adapted to iit snugly around the hose I0, embracing the braided sheath II thereof.

The fitting I4 in the form illustrated, comprises a cup portion l5 having a cylindrical cavity I6 therein of a diameter adapted slidably to receive the sleeve I3, and the iiexible hose I0 embraced thereby. A rear portion II, which can be externally threaded to permit its assembly with other structures, includes a bore I8 communicating with the cavity I6 and of a diameter approximating the inside diameter of the iiexible tubing I2.

In order to secure the fitting4 Il to the end of iiexible metal hose I0, the sleeve I3 is placed over the end of the hose and slid rearwardly thereon as illustrated in Fig. 4. The braided sheath II and the tubing I2 are cut off so that their ends will normally be aligned. When cut, the end of the sheath may flare outward as indicated at I9 in Fig. 4. The sleeve I3 is then advanced on the hose I0 until its end is flush with the cut end of the hose. as shown in Fig. 2, thereby confining the flared portion I 9 of the sheath against the hose, in its original condition.

An aluminum pin 20, having a shaft 2| conforming in diameter to the bore I8 of the fitting I4, is inserted in said bore from the rear end of the tting, so that it extends into the cavity I6. The shaft 2I preferably extends beyond the cup portion I5 of the fitting,

A quantity of solder 22 is placed in the cup of the tting, and is heated if necessary, for example by induction heating or by direct application of a flame to melt the solder and maintain it in molten condition. The pin 20 prevents the solder from running out of the cavity I6 through bore I8. It is also advantageous in some cases to preheat the end of the iiexible hose and sleeve I3 surrounding the same, to prevent too rapid cooling of the solder in the ensuing assembly operation.

The hose I0 and sleeve I3 are inserted downwardly into the cup portion I5 of the iitting so as to immerse the hose and sleeve in the solder and displace the same upwardly, the shaft 2| of pin 20 entering the end of the hose. The solder 22 rises upon such displacement, aided by capillary attraction, l-r-tween the sleeve I3 and the adjacent inside wail of the cavity I6, and also rises between the sleeve I3 and the sheath II entering the interstices of the braid. At the base of the cavity I6 the solder bonds to the end of the flexible tubing l 2, which is immersed therein. When the assembly has cooled suiiiciently to solidify the solder, the pin 20 is removed.

It will be observed that ythe braided sheath II, the sleeve I3 and tubing I2 are all firmly bonded together and to the fitting I4 by the solder, without the necessity of risking excessive heating and consequent injury to the metal of the sheath I I ing substantially beyond the cup portion I5 to the fitting, provides desirable support, reinforcing the soldered bond against undue strain from exure of the hose.

In making up connections according to previously known methods, omitting the sleeve I3 of my invention, the diiilculty encountered in inserting the end of thehhose into the cup portion oi the fitting by real-fin of expansion of the braid required individual manipulation for each connection, which rendered the operation impractical for mass production.

'I'he operations involved in assembling the hose and the ftting-in accordance with my invention can be readily carried out on a series of lengths of hose with great facility in a continuous manner,I since assembly of the sleeve with the hose, as

well as insertion of the hose and sleeve in thc fitting presents no dificulty and is adapted to be succession.

Other forms of ttings than the ones illustrated in the drawings can be employed, having a cup portion or similar structure for receiving the solder, and enclosing the end of the hose and the sleeve.

Variations and modifications may be made within the scope of this invention and portions of the improvements may be used without others.

I claim:

1. In combination with iiexible metal hose having a sheath of wire braid, a tting having a cylindrical cavity enclosing the end of the hose. a thin cylindrical metal sleeve embracing the hose and its sheathfat the end thereof and slidably fitting into said cylindrical cavity, and a mass of solder bonding the tubing of said hose to the base of said cavity, forming a bond between said sleeve and braided sheath as well as between said tting and said sleeve, and entering the interstices of the braided sheath.

2. The method of securing the end of a composite metal article including an innerl member and an outer expansible sheath of wire braid closely embracing the inner member to a body having a cylindrical cup-shaped article-receiving cavity which comprises positioning on the end of the article a thin metal sleeve adapted to t slidably within said cup-shaped cavity and snugly embrace the inner member and its braided sheath to prevent expansion of said sheath, providing a mass of molten solder in the base of the cavity, inserting the assembled sleeve and composite article into the cavity so as to immerse the end of the article in the. solder, and displacing a portion of the solder to cause it to rise between said sleevel gni said sheath and between said sleeve and said STEPHEN GUARNASCHELLI.

REFERENCES CITED vThe following referenlces are of record in the file of this patent:

v UNITED STATES PATENTS Number 

